Study On The Relationship Between Soil Nutrients And Species, Rare Earth Elements Enrichment Capacity Of Bryophytes In The Bayan Obo Mining Area

Bayan Obo Mining Area is located in the desert steppe climate zone and is an important rare earth base in China.Due to long-term exploitation and utilization,the ecological environment in this area has been destroyed.Bryophytes are important surface covering plants in arid and semi-arid desert areas,which play an important role in preventing wind and fixing sand,forming soil and retaining water,and have special ecological functions of enriching rare earth and heavy metal.In order to understand the characteristics of the main nutrients and mineral nutrient contents in the soil of the Bayan Obo Mining Area(MO?WO?EO)and the Periphery Areas(MDL?BLM?RTH?HSE),and to explore the relationship between bryophyte species,distribution,rare earth element enrichment and soil nutrients,this paper investigated the community composition and total coverage of bryophytes in the Bayan Obo Mining Area and the Periphery Areas.And this paper have determined the contents of main nutrients and mineral elements in the soil under and outside the moss clams of bryophytes.The experimental results showed:(1)The total coverage of bryophytes at various points in the study area ranged from 1.48% to 3.42%.The dominant genus is the Didymodon Hedw of the Pottiaceae.(2)The soil in the mining area is alkaline.Except for total phosphorus,organic matter,total potassium and total nitrogen in the mining area all showed a tendency of being smaller than the periphery of the mining area.The content of 8 mineral elements was higher in the mining area than in the periphery of the mining area.(3)The content of main nutrients and mineral elements in the soil under the moss cluster is significantly different from that in the outer soil.The content of most nutrients was higher in the lower soil than in the outer soil of moss cluster,and the mineral elements were lower in the lower soil than in the outer soil.(4)pH value was negatively correlated with organic matter,total nitrogen,total phosphorus,available phosphorus and available potassium,while there was a significant positive correlation between organic matter and most nutrients.Total potassium was significantly positively correlated with total nitrogen,available potassium was significantly positively correlated with alkali-soluble nitrogen and total nitrogen,and total phosphorus was significantly negatively correlated with both alkali-soluble nitrogen and total nitrogen.S has significant positive correlation with Fe,Ca,Mn,Zn and Mg,and significant negative correlation with B.B is negatively correlated with Zn,Fe,Ca and Mn.There was a significant positive correlation between Fe,Ca,Mn,Zn and Mg.Cu has no significant correlation with other elements.(5)Bryophyte coverage was positively correlated with soil organic matter,total potassium and total nitrogen,and negatively correlated with Mg,Ca,Fe and Mn.There was no significant correlation between the number of bryophyte species and the content of soil main nutrients in different regions.(6)The total amount of rare earth elements in bryophytes has a significant positive correlation with total nitrogen,alkali-soluble nitrogen and total phosphorus in soil,and has a significant negative correlation with total potassium and organic matter content,and has a significant positive correlation with Mg,Ca,Fe,Mn and Zn.In conclusion,bryophytes can promote the accumulation of major soil nutrients,especially organic matter,total potassium and total nitrogen can significantly increase the coverage of bryophytes.The main soil nutrients had no significant effect on the number and distribution of bryophytes.Total nitrogen alkali-soluble nitrogen and total phosphorus in soil can promote the enrichment of rare earth elements by bryophytes.The high content of Mg,Ca,Fe and Mn in the soil of the mining area is not conducive to the growth of bryophytes and the enrichment of rare earth elements by mosses.